Answer:
Explanation:
Liquid-liquid extraction is a very useful method to separate components from a mixture. It consists of separating one or several substances dissolved in a solvent by transferring them to another solvent insoluble or partially insoluble in the first. The transfer of matter is achieved by direct contact between the two liquid phases.
For the extraction process, the solution is placed in a separating funnel, a water-immiscible organic solvent is added (ethyl ether is the most used), the solution with the compound to be separated, the funnel is covered and the funnel is top. Then it shakes. Depending on the solubilities and density, different layers are observed. The denser the compound, the more it will sink.
Since the organic compound is usually much more soluble in ether than in water, most of the organic compound will be dissolved in the ether phase (upper phase) and inorganic salts, which are not soluble in ether, will remain in the aqueous phase ( lower phase). Subsequently, by separating the separating funnel the two phases are separated, the organic phase is collected.
Occasionally, after stirring, the two immiscible liquids do not separate sharply, forming an emulsion in the intermediate zone. This is called the colloidal suspension of a liquid in another (system consisting of two or more phases, usually a liquid and another dispersed in the form of generally very fine solid particles). One of the reasons for the formation of an emulsion is when the two phases have similar densities. Then the relative density of the organic solvent and water cannot always be relied upon, although there are methods to facilitate the complete separation of the two phases.
Answer:
Percent error = 3.7%
Explanation:
Given data:
Density of Al cylinder = ?
Weight of cylinder = 18 g
Diameter = 1.3 cm
Height = 5.2 cm
Actual density of Al = 2.7 g/cm³
Percent error = ?
Solution:
First of all we will calculate the volume of cylinder through given formula.
V = πr²h
r = diameter /2
V = 22/7 × (0.65 cm)²× 5.2 cm
V = 22/7 × 0.4225cm²× 5.2 cm
V = 6.89 cm³
Now we will calculate the density.
d = m/v
d = 18 g/ 6.89 cm³
d = 2.6 g/cm³
Percent error:
Percent error = measured value - actual value /actual value × 100
Percent error = 2.6g/cm³ - 2.7g/cm³ /2.7g/cm³ × 100
Percent error = 3.7%
Negative sign shows that measured or experimental value is less than actual value.
Answer:
During cellular respiration, plants take in carbon dioxide from the air and break down stored glucose.
Explanation:
Before cellular respiration takes place in a plant, photosynthesis occurs and absorbs sunlight and carbon dioxide from the air. The process then produces oxygen and glucose, which are needed as the reactants for cellular respiration. Cellular respiration will break down the stored glucose to make energy to produce carbon dioxide and water. Then the cycle repeats itself.
Answer:
group, 6 or 16
Explanation:
as the group's progress going from the left of the table to the right of the the table, the valance electrons increase. although group 14 is split up by a ladder stair steppy thingy. the ones on the top take electrons, and the ones below give electrons.